opt: Move always_{true,false} out of the parser

2 files changed, 61 insertions, 50 deletions

diff --git a/src/opt.c b/src/opt.c
index 934a4b4..c80d584 100644
--- a/src/opt.c
+++ b/src/opt.c
@@ -45,6 +45,7 @@
 #include "ctx.h"
 #include "diag.h"
 #include "eval.h"
+#include "exec.h"
 #include "expr.h"
 #include "pwcache.h"
 #include <assert.h>
@@ -799,6 +800,15 @@ static struct bfs_expr *optimize_empty(struct opt_state *state, struct bfs_expr
 	return expr;
 }
 
+/** Optimize -{exec,ok}{,dir}. */
+static struct bfs_expr *optimize_exec(struct opt_state *state, struct bfs_expr *expr) {
+	if (expr->exec->flags & BFS_EXEC_MULTI) {
+		expr->always_true = true;
+	}
+
+	return expr;
+}
+
 /** Optimize -gid. */
 static struct bfs_expr *optimize_gid(struct opt_state *state, struct bfs_expr *expr) {
 	struct range *range = &state->facts_when_true.ranges[GID_RANGE];
@@ -892,6 +902,34 @@ static bfs_eval_fn *const opt_pure[] = {
 };
 
 /**
+ * Table of always-true expressions.
+ */
+static bfs_eval_fn *const opt_always_true[] = {
+	eval_fls,
+	eval_fprint,
+	eval_fprint0,
+	eval_fprintf,
+	eval_fprintx,
+	eval_prune,
+	eval_true,
+
+	// Non-returning
+	eval_exit,
+	eval_quit,
+};
+
+/**
+ * Table of always-false expressions.
+ */
+static bfs_eval_fn *const opt_always_false[] = {
+	eval_false,
+
+	// Non-returning
+	eval_exit,
+	eval_quit,
+};
+
+/**
  * Table of simple predicates.
  */
 static const struct {
@@ -940,6 +978,7 @@ static const struct {
 	// Primaries
 	{eval_access,   optimize_access},
 	{eval_empty,    optimize_empty},
+	{eval_exec,     optimize_exec},
 	{eval_gid,      optimize_gid},
 	{eval_samefile, optimize_samefile},
 	{eval_type,     optimize_type},
@@ -964,6 +1003,20 @@ static struct bfs_expr *optimize_expr_lookup(struct opt_state *state, struct bfs
 		}
 	}
 
+	for (size_t i = 0; i < BFS_COUNTOF(opt_always_true); ++i) {
+		if (opt_always_true[i] == expr->eval_fn) {
+			expr->always_true = true;
+			break;
+		}
+	}
+
+	for (size_t i = 0; i < BFS_COUNTOF(opt_always_false); ++i) {
+		if (opt_always_false[i] == expr->eval_fn) {
+			expr->always_false = true;
+			break;
+		}
+	}
+
 	for (size_t i = 0; i < BFS_COUNTOF(opt_preds); ++i) {
 		if (opt_preds[i].eval_fn == expr->eval_fn) {
 			infer_pred_facts(state, opt_preds[i].pred);
@@ -1026,9 +1079,11 @@ static struct bfs_expr *optimize_expr_recursive(struct opt_state *state, struct
 	}
 
 	if (expr->always_true) {
+		expr->probability = 1.0;
 		set_facts_impossible(&state->facts_when_false);
 	}
 	if (expr->always_false) {
+		expr->probability = 0.0;
 		set_facts_impossible(&state->facts_when_true);
 	}
 
diff --git a/src/parse.c b/src/parse.c
index 0b4224c..5766237 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -86,26 +86,15 @@ struct bfs_expr *bfs_expr_new(bfs_eval_fn *eval_fn, size_t argc, char **argv) {
 	expr->persistent_fds = 0;
 	expr->ephemeral_fds = 0;
 	expr->pure = false;
+	expr->always_true = false;
+	expr->always_false = false;
 	expr->cost = FAST_COST;
+	expr->probability = 0.5;
 	expr->evaluations = 0;
 	expr->successes = 0;
 	expr->elapsed.tv_sec = 0;
 	expr->elapsed.tv_nsec = 0;
 
-	if (eval_fn == eval_true) {
-		expr->always_true = true;
-		expr->always_false = false;
-		expr->probability = 1.0;
-	} else if (eval_fn == eval_false) {
-		expr->always_true = false;
-		expr->always_false = true;
-		expr->probability = 0.0;
-	} else {
-		expr->always_true = false;
-		expr->always_false = false;
-		expr->probability = 0.5;
-	}
-
 	// Prevent bfs_expr_free() from freeing uninitialized pointers on error paths
 	if (bfs_expr_is_parent(expr)) {
 		expr->lhs = NULL;
@@ -197,21 +186,6 @@ static struct bfs_expr *new_binary_expr(bfs_eval_fn *eval_fn, struct bfs_expr *l
 }
 
 /**
- * Set an expression to always return true.
- */
-static void expr_set_always_true(struct bfs_expr *expr) {
-	expr->always_true = true;
-	expr->probability = 1.0;
-}
-
-/**
- * Set an expression to never return.
- */
-static void expr_set_never_returns(struct bfs_expr *expr) {
-	expr->always_true = expr->always_false = true;
-}
-
-/**
  * Color use flags.
  */
 enum use_color {
@@ -462,7 +436,6 @@ static bool parse_expr_warning(const struct parser_state *state, const struct bf
  * Fill in a "-print"-type expression.
  */
 static void init_print_expr(struct parser_state *state, struct bfs_expr *expr) {
-	expr_set_always_true(expr);
 	expr->cost = PRINT_COST;
 	expr->cfile = state->ctx->cout;
 	expr->path = NULL;
@@ -1359,9 +1332,7 @@ static struct bfs_expr *parse_exec(struct parser_state *state, int flags, int ar
 
 	expr->exec = execbuf;
 
-	if (execbuf->flags & BFS_EXEC_MULTI) {
-		expr_set_always_true(expr);
-	} else {
+	if (!(execbuf->flags & BFS_EXEC_MULTI)) {
 		expr->cost = 1000000.0;
 	}
 
@@ -1395,7 +1366,6 @@ static struct bfs_expr *parse_exit(struct parser_state *state, int arg1, int arg
 
 	struct bfs_expr *expr = parse_action(state, eval_exit, argc);
 	if (expr) {
-		expr_set_never_returns(expr);
 		expr->num = status;
 	}
 	return expr;
@@ -1525,7 +1495,6 @@ static struct bfs_expr *parse_fls(struct parser_state *state, int arg1, int arg2
 		goto fail;
 	}
 
-	expr_set_always_true(expr);
 	expr->cost = PRINT_COST;
 	return expr;
 
@@ -1540,7 +1509,6 @@ fail:
 static struct bfs_expr *parse_fprint(struct parser_state *state, int arg1, int arg2) {
 	struct bfs_expr *expr = parse_unary_action(state, eval_fprint);
 	if (expr) {
-		expr_set_always_true(expr);
 		expr->cost = PRINT_COST;
 		if (expr_open(state, expr, expr->argv[1]) != 0) {
 			goto fail;
@@ -1559,7 +1527,6 @@ fail:
 static struct bfs_expr *parse_fprint0(struct parser_state *state, int arg1, int arg2) {
 	struct bfs_expr *expr = parse_unary_action(state, eval_fprint0);
 	if (expr) {
-		expr_set_always_true(expr);
 		expr->cost = PRINT_COST;
 		if (expr_open(state, expr, expr->argv[1]) != 0) {
 			goto fail;
@@ -1595,8 +1562,6 @@ static struct bfs_expr *parse_fprintf(struct parser_state *state, int arg1, int
 		return NULL;
 	}
 
-	expr_set_always_true(expr);
-
 	expr->cost = PRINT_COST;
 
 	if (expr_open(state, expr, file) != 0) {
@@ -2373,23 +2338,14 @@ static struct bfs_expr *parse_printx(struct parser_state *state, int arg1, int a
  */
 static struct bfs_expr *parse_prune(struct parser_state *state, int arg1, int arg2) {
 	state->prune_arg = state->argv;
-
-	struct bfs_expr *expr = parse_nullary_action(state, eval_prune);
-	if (expr) {
-		expr_set_always_true(expr);
-	}
-	return expr;
+	return parse_nullary_action(state, eval_prune);
 }
 
 /**
  * Parse -quit.
  */
 static struct bfs_expr *parse_quit(struct parser_state *state, int arg1, int arg2) {
-	struct bfs_expr *expr = parse_nullary_action(state, eval_quit);
-	if (expr) {
-		expr_set_never_returns(expr);
-	}
-	return expr;
+	return parse_nullary_action(state, eval_quit);
 }
 
 /**